RT Journal Article SR Electronic T1 Response JF Journal of Medical Ethics JO J Med Ethics FD BMJ Publishing Group Ltd and Institute of Medical Ethics SP 95 OP 95 DO 10.1136/jme.8.2.95 VO 8 IS 2 A1 Robert G Twycross YR 1982 UL http://jme.bmj.com/content/8/2/95.abstract AB